Of course, there are no guarantees that such developers will emerge and save ReMail. Last year, when Google decided to cease work on the Twitterlike Jaiku service it had bought, it released Jaiku as open-source code–and that’s pretty much the last time Jaiku attracted attention at all. But ReMail is a unique, useful product with a clear audience. Maybe someone out there will see an opportunity to make money by rescuing it–I hope so.

And then he shares news that doesn’t sound all that thrilling to me: Google has discontinued reMail and yanked it off the iPhone App Store. Previously-downloaded copies will still work, and users of the free version can get all the features of the paid edition. But Google will stop supporting the app at the end of next month, and there will never be another update. Starting today, reMail is a Dead App Walking.

Oddly enough, Cselle says all this on a blog with a profile that says that (A) reMail exists to radically improve mobile e-mail; and (B) it hasn’t launched yet. That’s out of date on both fronts: It did launch–in beta form, at least, to an enthusiastic reception–and it won’t be improving e-mail from here on out.

Cselle doesn’t explain why Google is killing reMail. It’s possible that the company remained impressed by Cselle and wasn’t interested in reMail itself. But it’s also conceivable that it sees reMail as the foundation of an ambitious Gmail app, and that everything that was cool about reMail will reappear at some point in a new form. We just don’t know, and Google doesn’t seem to be dropping hints.

The search-engine behemoth has acquired an infinite number of interesting startups over the years. In certain cases, that’s been good news for fans of the products those companies made–Google Earth (nee Keyhole 3D Earth Viewer) and Picasa spring to mind. (Oh, and YouTube.) And Google says that the neat Q&A service Aardvark, which it bought last week, will live on as a Google Labs project.

Unfortunately, though, what’s good news for Google and startup founders is often a bummer–at least in the short term–for everyone else who cared about the startup in question.